The police officer who died trying to stop a mass shooting rampage at the Borderline Bar & Grill in Thousand Oaks, Calif., in November was killed by friendly fire, authorities have concluded.

Ventura County Sheriff's Sgt. Ron Helus was one of the first officers to respond to the scene when Ian David Long, 28, burst into the bar on the night of Nov. 7, set off a smoke device and began firing into the patrons who had assembled there for a country college night. Twelve people died, including Helus, who suffered six gunshot wounds.

CNN reports that at a press conference Friday morning (Dec. 7), Sheriff Bill Ayub revealed that five of those shots came from Long's gun, but Helus was also struck by one bullet fired from the rifle of a California Highway Patrol officer. Authorities have concluded that Helus might have survived the other wounds and that the rifle shot was the one that killed the first responder.

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Ventura County Medical Examiner Dr, Christopher Young says the shot from the rifle struck Helus in his heart, characterizing it as the "most lethal wound" Helus sustained during the exchange of gunfire.

Helus was a 29-year law enforcement veteran who was slated to retire next year. He leaves behind a wife and son. At a press conference after Helus' death, Ventura County Sheriff Geoff Dean lauded the officer's courage.

"He went in to save lives, to save other people," Dean said. "He was totally committed, he gave his all, and tonight, as I told his wife, he died a hero."

The shooter also died at the scene in what authorities believe was a suicide. No motive has yet been revealed for the crime. According to USA Today, Sheriff Ayub placed the responsibility for Helus' death on Long.


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